The Collaborative International Dictionary of English v.0.48:

Jasper \Jas"per\, n. [OE. jaspre, jaspe, OF. jaspre, jaspe, F.
   jaspe, L. iaspis, Gr. ?; cf. Per. yashp, yashf, Ar. yashb,
   yasb, yasf, Heb. y[=a]shpheh. Cf. Diaper.] (Min.)
   An opaque, impure variety of quartz, of red, yellow, and
   other dull colors, breaking with a smooth surface. It admits
   of a high polish, and is used for vases, seals, snuff boxes,
   etc. When the colors are in stripes or bands, it is called
   striped jasper or banded jasper. The Egyptian pebble is a
   brownish yellow jasper.
   [1913 Webster]

   Jasper opal, a yellow variety of opal resembling jasper.

   Jasper ware, a delicate kind of earthenware invented by
      Josiah Wedgwood. It is usually white, but is capable of
      receiving color.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Wedgwood ware \Wedg"wood` ware`\ [From the name of the inventor,
   Josiah Wedgwood, of England.]
   A kind of fine pottery, the most remarkable being what is
   called jasper, either white, or colored throughout the
   body, and capable of being molded into the most delicate
   forms, so that fine and minute bas-reliefs like cameos were
   made of it, fit even for being set as jewels.
   [1913 Webster]

WordNet (r) 3.0 (2006):

jasper
    n 1: an opaque form of quartz; red or yellow or brown or dark
         green in color; used for ornamentation or as a gemstone